[PATCH V2 07/13] block: move q_usage_counter release into blk_queue_release

[Ming Lei]

After blk_cleanup_queue() returns, disk may not be released yet, so
probably bio may still be submitted and ->q_usage_counter may be
touched, so far this way seems safe, but not good from API's viewpoint.

Move the release ofq_usage_counter into blk_queue_release().

Signed-off-by: Ming Lei <ming.lei at redhat.com>
---
 block/blk-core.c  | 2 --
 block/blk-sysfs.c | 2 ++
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index d9477191b303..bcb4d982cd80 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -341,8 +341,6 @@ void blk_cleanup_queue(struct request_queue *q)
 		blk_mq_sched_free_rqs(q);
 	mutex_unlock(&q->sysfs_lock);
 
-	percpu_ref_exit(&q->q_usage_counter);
-
 	/* @q is and will stay empty, shutdown and put */
 	blk_put_queue(q);
 }
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 6f326b44fb00..5f14fd333182 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -780,6 +780,8 @@ static void blk_release_queue(struct kobject *kobj)
 
 	might_sleep();
 
+	percpu_ref_exit(&q->q_usage_counter);
+
 	if (q->poll_stat)
 		blk_stat_remove_callback(q, q->poll_cb);
 	blk_stat_free_callback(q->poll_cb);
-- 
2.31.1